#ifndef LINUX_HARDIRQ_H
#define LINUX_HARDIRQ_H

#include <linux/config.h>
#include <linux/preempt.h>
#include <linux/smp_lock.h>
#include <asm/hardirq.h>
#include <asm/system.h>

/*
 * We put the hardirq and softirq counter into the preemption
 * counter. The bitmask has the following meaning:
 *
 * - bits 0-7 are the preemption count (max preemption depth: 256)
 * - bits 8-15 are the softirq count (max # of softirqs: 256)
 *
 * The hardirq count can be overridden per architecture, the default is:
 *
 * - bits 16-27 are the hardirq count (max # of hardirqs: 4096)
 * - bit 28 is the PREEMPT_ACTIVE flag
 *
 * PREEMPT_MASK:         0x000000ff
 * SOFTIRQ_MASK:         0x0000ff00
 * HARDIRQ_MASK:         0x0fff0000
 * PREEMPT_ACTIVE_MASK:  0x10000000
 */
#define PREEMPT_BITS		8
#define SOFTIRQ_BITS		8
#ifndef HARDIRQ_BITS
#define HARDIRQ_BITS		12

/*
 * The hardirq mask has to be large enough to have space for potentially
 * all IRQ sources in the system nesting on a single CPU.
 */
#if (1 << HARDIRQ_BITS) < NR_IRQS
# error HARDIRQ_BITS is too low!
#endif
#endif
#define PREEMPT_ACTIVE_BITS	1

#define PREEMPT_SHIFT		0
#define SOFTIRQ_SHIFT		(PREEMPT_SHIFT + PREEMPT_BITS)
#define HARDIRQ_SHIFT		(SOFTIRQ_SHIFT + SOFTIRQ_BITS)
#define PREEMPT_ACTIVE_SHIFT	(HARDIRQ_SHIFT + HARDIRQ_BITS)

#define __IRQ_MASK(x)		((1UL << (x))-1)

#define PREEMPT_MASK		(__IRQ_MASK(PREEMPT_BITS) << PREEMPT_SHIFT)
#define SOFTIRQ_MASK		(__IRQ_MASK(SOFTIRQ_BITS) << SOFTIRQ_SHIFT)
#define HARDIRQ_MASK		(__IRQ_MASK(HARDIRQ_BITS) << HARDIRQ_SHIFT)

#define PREEMPT_OFFSET		(1UL << PREEMPT_SHIFT)
#define SOFTIRQ_OFFSET		(1UL << SOFTIRQ_SHIFT)
#define HARDIRQ_OFFSET		(1UL << HARDIRQ_SHIFT)

#if PREEMPT_ACTIVE < (1 << (HARDIRQ_SHIFT + HARDIRQ_BITS))
# error PREEMPT_ACTIVE is too low!
#endif

#define hardirq_count()	(preempt_count() & HARDIRQ_MASK)
#define softirq_count()	(preempt_count() & SOFTIRQ_MASK)
#define irq_count()	(preempt_count() & (HARDIRQ_MASK | SOFTIRQ_MASK))
#define irqs_off()	(current->flags & PF_IRQSOFF)

/*
 * Are we doing bottom half or hardware interrupt processing?
 * Are we in a softirq context? Interrupt context?
 */
#define in_irq()	(hardirq_count() || (current->flags & PF_HARDIRQ))
#define in_softirq()	(softirq_count() || (current->flags & PF_SOFTIRQ))
#define in_interrupt()	(irq_count())

#if defined(CONFIG_PREEMPT) && \
	!defined(CONFIG_PREEMPT_BKL) && \
		!defined(CONFIG_PREEMPT_RT)
# define in_atomic()	((preempt_count() & ~PREEMPT_ACTIVE) != kernel_locked())
#else
# define in_atomic()	((preempt_count() & ~PREEMPT_ACTIVE) != 0)
#endif

#ifdef CONFIG_PREEMPT
# define preemptible()	(preempt_count() == 0 && !irqs_disabled())
# define IRQ_EXIT_OFFSET (HARDIRQ_OFFSET-1)
#else
# define preemptible()	0
# define IRQ_EXIT_OFFSET HARDIRQ_OFFSET
#endif

#ifdef CONFIG_SMP
extern void synchronize_irq(unsigned int irq);
#else
# define synchronize_irq(irq)	barrier()
#endif

#define nmi_enter()		/* irq_enter() */
#define nmi_exit()		/* sub_preempt_count(HARDIRQ_OFFSET) */

#ifndef CONFIG_VIRT_CPU_ACCOUNTING
static inline void account_user_vtime(struct task_struct *tsk)
{
}

static inline void account_system_vtime(struct task_struct *tsk)
{
}
#endif

#define irq_enter()					\
	do {						\
		account_system_vtime(current);		\
		add_preempt_count(HARDIRQ_OFFSET);	\
	} while (0)

extern void irq_exit(void);

#endif /* LINUX_HARDIRQ_H */
